Blind Optical Modulation Format Identification From Physical Layer Characteristics

Abstract—We describe and experimentally demonstrate auto-mated identification of optical modulation formats exclusively from physical-layer signal characteristics. The system identifies the data encoding as on–off keyed versus binary or quadrature phase-shift keyed, as well as auxiliary modulation profiles. The symbol clock rate and optimal dispersion compensation are also determined. We have validated this system with over 1500 test cases. These are enabling functionalities for a universal optical receiver and for a cognitive optical network architecture that optimizes utilization of available optical bandwidth. We demonstrate the capabilities of the system using a wavelength division multiplexed signal consisting of 19 channels, with multiple modulation formats and widely varying dispersions, signal strengths, and optical signal-to-noise ratios. Index Terms—Coherent communications, fiber optics commu-nications, optical modulation. I